Typewriting machine



Aug. 30, '1932. w. A. -DoBsoN 1,874,255

` l TYPEWRITING. MACHINE Filed April 4, 1929 /r/'gj y WAL'.\\\\\\\\\\\\\\\\\\\\\\\\\\\\x Patented Aug. 30, 1932 UNITED STATESPATENT OFFICE' WILLIAM A.DOBSON, 0F BRIDGEPOBT, CONNECTICUT, ASSIGNORrTO 'UNDERWOOD EL- l' LIOTT FISHER COMPANYQOF NEW YORK, N. Y., ACORPORATION 0F DELAWARE TYPEWRTTING MACHINE `Application ,legdy April 4,1929. Serial No. 352,377.

This invention relates to typewriting machines, and more particularly tomeans for instantly connecting or disconnecting Vthe ratchet-wheel andplaten.

In portable typewriting machines, the platen-carriage just its betweenthe sides of the carrying case cover. In Vconstructing the presentinvention, it is aimed to arrange the mechanism so that the widthbetween the left and right platen `knobs,-wh'ich arethe extreme outerends of the platen-carriage, should not be extended; n

For this purpose, the releasing mechanism is constructedto fit betweenthe platen and the left-hand "carriage-end plate; and for compactnessthe releasing mechanism is constructed to extend within the platen, sothat the entire mechanism takes up only a small amount of space outsideof the platen.

Shortening yof vthe typing line has been avoided, while the distancebetween the carriageeend plates has remainedv the same.

The construction requires practically no changes in the standardconstruction of the L Underwood portable typewriter-carriage.

Another feature is that the clutch-mechanism may be operated from eitherside of the carriage by merely operating either the left or rightplaten-knob. f

In these portable typewriters the length of the carriage is limited,while the platen is constructed as long as ossible, .so as to accomodatea wide sheet. n devising the. present invention it was necessary thatthe carriage should not be lengthened, and that the writing line shouldnot be shortened, and furthermore that the usual wide sheet should stillbe filled out with typed lines. The clutchfreleasing mechanism takes uponly the space between the platen and the line-space ratchet-wheel,which, in the present invention, forms the outer end of saidclutch-mechanism.

There is used a slidable platen-shaft carrying the platen-knobs.yMovement of theshaft L' is one direction wedges apart theclutch-segments, whichengage and bind' a drum provided on theratchet-wheel.

lVhen the platen-shaft is moved in a reverse direction, the wcdgingmeans Vwill release the clutch-segments from the drum of the ratchetwheel, which disassociates the platen therefrom, and permits independentspacing of a work-sheet. Through the simplicity of the clutching meansemployed, it is necessary to exert but a slight pressure on oppositeplatenknobs, in order to alternately make the ratchet-wheel effectiveorineffective. It is tantamount also that instead of pressing onoppositeknobs, the same results are accomplished by alternately pressingand pulling on only one knob. For this'reason the connection or releaseof the ratchet-wheel can be easily controlled from thatend of thecarriage which is most convenient to reach.

Another feature of this invention lies in the 'double functionincorporated in the wedge, which forces the clutch-segments apart, andconcomitantly locksthem in tight frictional engagement with theratchet-wheel drum.

Due to the springiness of said segments, the wedge sets up tensiontherein, which aids in increasing the friction by slightly flatteningthe curves and increasing their holding area. Said springiness alsocauses the segments to better fill out any'inequalities on the innersurface of the drum, and thus helps to main'- tain frictionalengagement. A 'Y e Another feature of this inventien lies'inthe usey ofa retaining pinwhich acts as a`fulcrurnforthe wedge, and also holds theclutchsegments in "effective alignment therewith. In assembling the pinandthe wedge, thelatter is bored to have a driving it` for the pin,whereby the pin is held Vafter insertion. In order to permit rotation ofthe pin when the wedge is swung, the pin-retaining holes of the segmentsare bored somewhat larger than the pin. These larger Vholes also provideclearance for the segments, so the latter can move along the pin whenspread or released by the wedge. Y e Other features and advantages willhereinafter appear. i f

In the accompanying drawing, Figure 1 isa partial longitudinalsectionthrough aplaten and its supports, and shows the parts of this inventionas related when the ratchet-wheel is ineffective. v

l Figure v2 isa perspective view of a portion of a platen, and showssome of the parts of 1 this invention associated therewith, andpartially broken away.

Figure 3 is a` partial longitudinal section througha platen, and showsparts of this invention as related when the ratchet-wheel has been madeeffective.

Figure 4 is a detail of parts of the clutch` and shows the segmentsforced apart by the wedge.

Y Figure 5 isa Ysimilar view to Figure 4, but' with the wedge partiallywithdrawn to permit the release of the ratchet-wheel.V

Figure 6 is a perspective view'ot parts of this invention, and in properrelationship for assembly.

Figure 7 is aperspective View of parts of this invention, and shows theadjustable devicefor raising or lowering one end of the platen-shaft.

Figure 8 is a perspective detail ot the pivoted wedge, the amount ofslope in the wedged faces being indicated in dot and dash.

Referring to the drawing, 10 and 11 are end frames ofa platen-carriage,which form Vpart of a typewriter, not shown. The frame 10 has acountersunk hole 12, in which is inserted a journal 13. The latterhas ashoulder 14 and a turned-down portion 15 which is riveted to the frame.The trame 11 has a clearance hole 16 and an approximately horizrontalslot 17 through which projects a setscrew 18 that is threaded into ablock 19. The latter is slidable between two lugs 20 which are attachedto or are integral with the frame l1.

In the block 19 is an inclined slot 21, in which can slide the roundedhead 22 of a lever 23 which is attached to the frame 11 by a pivot 24.The lever 23 has a countersunk hole 25 in which is inserted a journal26. The latter has a shoulder 27 ,and a turned-down portion 28 which isriveted to the lever 23. The journal 26 supports a platen-shaft 29 whichis slidable therethrough, and which has a flattened area 30. The latteris abutted by a set-screw 31 which attaches a platenknob32through'gmeans of a connected hub 33.

A set-collar 34 is mounted on the journal 26 and adjustably abuts a hub35 which forms part of a usual end plate 36. VThe latter is attached byscrews 37 to a core 38 which forms part of a platen 39. The latter alsohas an end plate 40 which is attached to saidV core by screws 41. Saidend plate 40 is formed with an inwardly-extending barrel 42 which isaxially bored and in which can slide a cylinder 43. The latter has abeveled end 44 to remove any burr that might impede the sliding of saidcylinder.

The cylinder 43 is axially bored as at 45 to' support an end of theplaten-shaft 29 which is fixed therein through means of a pin 46. Saidcylinder also has al larger axial boring 47 which lightens its weightand provides clearance as will appear. The cylinder is slidablysupported in the journal 13 and is tightly held in a hub 48 of aplaten-knob 49. A pin 50 can also be used to hold said cylinder in saidhub. The cylinder has a channel 51, vat one end of which is a hole 52that extends through the wall.

The end plate 40 has a hub 53 which tightly its inside an end of thecore to center and help support the same. The fixity of the two is alsofurthered by a shoulder 54 which abuts the end of said core. The endplate 40 also has an annular bearing surface 55, a shoulder 56 Aand twohubs 57 and 58. The bearing surface55 supports one end of a rotatabledrum 59 whose other vend is turned down and .riveted over an innerbeveled edge of a on by a shoulder 63.

The plate 61 has a countersunk hole tor a screw 64 which has a shank 65,a shoulder 66 and a threaded portion 67. The latter is screwed into athreaded hole 68, in the end plate 40. The counter-sinking of the screw64 prevents the head from hitting extraneous parts when said plate isrotated, while the shoulder 66 limits the thrust and prevents theshoulder 63 from pinching the drum and arresting or retarding itsrotation. The shank also servesas a fulcrum for clutchsegments 70 whichhave approximately semicircular channels 71 that fit thereon.

The clutch-segments 7 0 can swing radially between the drum 59 and thehub 57. The latter also serves tol space the plate 61 from the shoulder56 which provides side clearance for the swing of said segments. Thelatter have holes 72 at one end that are larger than a retaining pin 73which they encompass. The segments therefore can swing radially asufficient distance before being stopped by said pin. At the ends havingthe holes 72 the segments are formed with cam-surfaces 73a whichnormally lie at an angle to each other and will abut a wedge 74.

The wedge 74 has a hole 75 of such diameter as will retain the pin 73when positioned therein. When assembled the holes 72 will fulcrum saidpin as the wedge is rotated through an attached lever 76. The pin alsoserves to maintain the wedge and the segments 70 in effective relativepositions. The lever 76 has a beveled end 77 and a rounded nose 78. Saidbevel permits the lever to slide along the channel 51 during assemblageof thel various parts of this invention. Said rounded nose presents asmooth surface to the side of the hole 52 so as'to slide easily whensaid side actuates the lever. During such movement the lever projectsthrough said hole and into the clearance space 47.

In forming the plate 61 the inner edge has a cut-out 7 9to permitswinging of the llever 76. For the same reason the end plate 40 also hasa cut-out 80. In' addition there is a spacing collar 81 between thelframe 10 and the end of the; hub 58. Said' collarmaintains a clearancespace for parts of the pawl, not shown. A spring-,pressed detent82 isalso shown, as well as a type-head 83. The spacing lever and associatedparts, while used with this invention, are common, and for this reasonhave not been shown.

In lassembling the parts of this invention the components of the bearingon the end plate 11 can be installed first. The platen is then mounted*on its end plates, while the ratchet-wheel and clutch-members areplaced in relative association with the endV plate 40.' The screw 64 isthen threadedinto the hole 68 to secure the plate 61, and `is fixed bytight ,abutment of the shoulder 66 against the end plate 40 which haspreviously been inserted and adjusted for this purpose. The knob 49 andthe platen-shaft 29 having been attached to the cylinder 43, theseunified components are successively run through the journal 13 and thespacing collar `81. j A

As the platen-shaft passes the collar 81 it is run through the platen,which at this time is held centered between the journals 13 and 26.During the transition of the unified shaft, the inwardly-projectinglever 76k will slide along the channel `51 until the nose 78 abuts theend thereof. The set-collar 34'can then be adjusted to abut the endplate 36 vto hold the end plate f40 in rotatable abutment` with thespacing collar 81. Without disturbing the relative positions of thecylinder 43 and the lever 76, the knob 32 is attached to theplaten-shaft and in the position shown in Figure 1.

The platen having been mounted in the carriage, it is adjusted ifnecessary to bring its axis parallel to the line of typing. This isusually accomplished, as previously mentioned, through means of theblock 19. It is not wished, however, to limit this invention to the useof only one block, because the same adjusting device in modified formcan also be installed at the other end of the carriage. With said deviceat 'each end of the carriage it is then possible to iiX the platen invarious horizontal planes, and thus vary the angleV at which theplaten-surface is struck by the type.

Besides spreading and locking the clutchsegments apart, the wedgingmeans maintains the associated cylinder and end plate'in fixed rotativerelation. This is accomplished'by the lever of the wedge which passesthrough the walls of said cylinder and plate. As the lever requires butslight clearance. to swing through said walls, lost motion is minimizedwhen the superposed members are rotated by the cylinder. For this reasonthe dwell of said plate is negligible when actuated by the 'Y lever andthey rotate in unison. Therefore during rotation of the releasedclutch-members, the wedge does not creep to press a segment against thedrum, and the ratchet-wheel remains ineffective.

The drawing illustrates this invention as applied toa portable'typewriter having a platen-shaft ofsmall diameter. Due to the latter,the cylinder 43 is used to provide an enlarged end that can be machinedand still have structural strength. Because the cylinder supports oneend of the platen, itforms part of the platenshaft, and if omitted willnot nullify this invention. When omitted, a larger shaft is used, thechannel 51 is eliminated, the clearance space 47 and hole 52 areincorporated, the cut-out 79 is deepened and the leve-r 76 islengthened. The assembling is then virtually the same excepting thatbefore final lengthwise setting of the shaft, said lever is projectedinto said space 47 This invention fthereforeis adaptable to largemachines and it is not desired to limit it to the design illustrated.

',Variationsmay be resorted to within the scope of the invention, andportions of the improvements lmay be used without others.

Having thus described my invention, I claim: f 1; In a typewritingmachine, the combination with a platen and a shaft, of a linespace wheelfreely rotatable about said shaft, a clutch-mechanism to connect saidline-space wheel with said platen and including a drum secured to saidline-space wheel, a pair of expansible grips having a driving connectionto the platen and curved to conform with the inner periphery of saiddrum, a wedging arm pivotally mounted between two adjacent ends ofsaidgrips, said arm having at one end a j pivot journaled in said grips,means engagingthe other end vof the arm with said shaft `for rotarytransmission thereby, and actuating means for swinging said armlongitudinally to expand said grips, thereby causing the grips to engagethe line-spacewheel drum, and allow the shaft to rotate the line-spacewheel together with the platen.

2. In a typewriting machine, 'the combi nationwith a platen havingplaten-ends conlined between the ends of a platen-frame, of a shaftaxially shiftable in `said platen-ends, a linespace wheel adjacent oneend ofthe Vplaten and freely rotatable about said shaft,

a clutch-mechanism to connect said line-space wheel with said platen andincluding a drum secured to said linespace wheel and rotatable upon theadjacent platen-end, a pair of grips having beveled adjacent tips andcurved to conform with the inner periphery of said drum, a member rigidupon said platen-end and upon whichone end of said grips may befulcrumed, an arm opposite to the fulcrumpoint and pivotally mountedbetween the otherends of said grips and having'a wedging surface toengage said beveled tips, and means upon said shaft to control said armas the shaft is shifted to expand said grips by awedging action, thuscausing the same v to engage the drum, said arm co-operating with saidcontrolling means to form a cou- -pling connectingsaid shiftable shaftto said grips, effective to allow the shaft to rotate the platen.

8. In a typewriting machine, the combination with a platen havingplaten-ends confined between the ends of a platen-frame, of a shaftaxially shift-able in vsaid platen ends, said shaft effective to rotatethe platen in every axial shift position of the shaft, a linespace wheelrotatable about said shaft, a drum rotatable together with saidline-space Vwheel about said shaft, expansible grips operable to bearagainst said drum to engage said linespace wheel, a wedge-memberpivotally mcuntedbetween two adjoining ends of said grips to cause saidgrips to engage said drum, said shaft having a recess in which the vfreeend of said wedge-member may lodge, so that itA may be swungA betweenoperative and idle position as the shaft is shifted, said wedgemember,in combination with Said recess, serving to rotate said grips togetherwith said shaft.

4. In a typewriting machine, the combination with a platen, a shaft, andline-space mechanism including a disengageable linespace wheel adjacentone end of said platen and rotatable relatively with said platen andshaft, of a clutch-mechanism connecting said platen and line-spacewheel, including a drum secured to said line-space wheel, grips curvedto conform with the inner periphery of said drum, an arm pivotallymounted between said grips and provided with a wedging surface, means onsaid shaft to swing said arm about its pivot and cause said wedgingsurface to press said grips against said drum, and a groove in saidshaft to receive the free end of said arm and form a path therefor, topermit the shaft to be removed from said mechanisms.

5. In a typewriting machine, the combination with a platen, a shaftslidably mounted within said platen, and a loose line-space wheeladjacent one end of said platen and rotatable relatively with saidplaten and shaft, of a clutch-mechanism connecting said platen andline-space Wheel, including a drum secured to said line-space Wheel,grips having beveled adjacent tips and curved to conform with the innerperiphery of said drum, an arm pivotally mounted between said grips, andhaving wedging portions to co-operate with said beveled tips, said armforming a driving connection between said platen and shaft, when thelatter is rotated, but permitting free horizontal movement in bothdirections ofsaid shaft with respect to said platen, and means on saidyshaft (3o-operating with vsaid arm in each direction of said horizontalmovement, to alternately connect and disconneet' the line-space Wheelfrom said platen.

. 6. In a typewriting machine, the combination of a platen, alongitudinally-adjustable shaft supporting the same, a line-space wheelnormally connected in operative engagement With said platen to rotatethe same, a clutching device mounted on the shaft, a controllertherefor, effective to engage and disengage the wheel from the platen atwill, and a pair of shoulders on said shaft, one at eac-h side of thecontroller, to control the operations of the clutching device by thelongitudinal reciprocating movements of said shaft, by direct mechanicalengagement with said clutching-device controller, said shaft alsoincluding means effective to rotate the platen when the latter isdisengaged from said wheel.

7. In a typewriting machine, the combination of a platen, a shaftsupporting the same, means for line-spacing the platen by the shaft,including a toothed wheel, a clutch mounted on the platen, effective toengage and disengage the-wheel with reference to said platen, saidclutch including a lever pivoted at one end thereto, effective tooperate the clutch, and a recess in the shaft to receive the other'endof the lever to engage the lever With'the shaft for swinging the leverinto clutch engaging and disengaging position alternately thereby, andeffective to engage the platen With said shaft for rotation in bothpositions of the lever.

' WILLIAM A. DOBSON.

